NRF54L15 - DFU over UART. Not able to update the Firmware.

RE: NRF54L15 - DFU over UART. Not able to update the Firmware.

Vidar Berg — Tue, 19 Aug 2025 06:54:47 GMT

Hi,

I'm glad to hear you found the problem, thank you for the update. I have made the same mistake of forgetting that I have disabled the COM port in the board configurator.

RE: NRF54L15 - DFU over UART. Not able to update the Firmware.

varsha@ — Tue, 19 Aug 2025 06:18:39 GMT

Hello,

I realized I had made a careless mistake—while testing sleep current earlier, I had disabled the COM ports in nRF Connect for Desktop. It only just occurred to me, and after enabling them again, everything is working properly now.

I'm sorry for taking up your time, and I truly appreciate your patience and support in helping me troubleshoot this.

Thank you.

RE: NRF54L15 - DFU over UART. Not able to update the Firmware.

Vidar Berg — Mon, 18 Aug 2025 13:01:19 GMT

It's strange that you are getting the timeout both when running in serial recovery mode in mcuboot and also in the app. I'm not able to reproduce this here either using the project you uploaded. Attached is the merged.hex file from my build. Please try it on your end and see whether it works or not.

Blinky built with SDK v3.0.2

devzone.nordicsemi.com/.../2477.merged.hex

RE: NRF54L15 - DFU over UART. Not able to update the Firmware.

varsha@ — Mon, 18 Aug 2025 12:46:40 GMT

Yes, I just tried the configs you provided. Still there is no change.

[quote userid="4240" url="~/f/nordic-q-a/123608/nrf54l15---dfu-over-uart-not-able-to-update-the-firmware/545921"]Does LED 0 start blinking after you flash the firmware, indicating that your Blinky app is running[/quote]

Yes, the LED 0 blinks every 1 second, and if I press button 1 + Reset button, The LED1 stays on and LED0 stops blinking. I tried to get the image list using mcumgr in both the "normal mode" as welll as in the "serial recovery mode" as I was not sure in which mode I should be using the mcumgr commands. I am getting the same Timeout error.

Same with the Auterm. I tried to get the Image -> Get -> Go after making configurations.

And the error was - Timeout (Mode: List image state)

RE: NRF54L15 - DFU over UART. Not able to update the Firmware.

Vidar Berg — Mon, 18 Aug 2025 12:19:06 GMT

Hello,

Does LED 0 start blinking after you flash the firmware, indicating that your Blinky app is running (or in mcuboot serial recovery mode)? Also note that when enabling SMP over UART in your app you need to make sure you don't have the console or logger module assigned to the same UART instance. I suggest you try with the following configurations added to your prj.conf file

CONFIG_UART_CONSOLE=n

CONFIG_LOG=y
CONFIG_LOG_BACKEND_UART=n
CONFIG_USE_SEGGER_RTT=y

RE: NRF54L15 - DFU over UART. Not able to update the Firmware.

varsha@ — Mon, 18 Aug 2025 10:59:38 GMT

Hello,

I tried to use mcumgr as well for DFU over UART. I am getting an error of NMP Timeout. I disabled the virtual Mass storage also.

Where must I be going Wrong?

Thankyou.

RE: NRF54L15 - DFU over UART. Not able to update the Firmware.

varsha@ — Mon, 18 Aug 2025 08:06:55 GMT

Hello,

Im sorry for the late reply.

I have tried on different Baudrates (115200 and 9600) and on both the COM Ports available. And yes, I also disabled the virtual mass storage.

I am getting the same Timeout error. I am attaching the code which I tried on the DK.

devzone.nordicsemi.com/.../1452.blinky.zip

RE: NRF54L15 - DFU over UART. Not able to update the Firmware.

Marte Myrvold — Tue, 12 Aug 2025 06:22:28 GMT

Hi,

In the nRF Connect SDK, we use SMP to transfer DFU images, so the device transmitting the image must act as an SMP client. I have not tried using TeraTerm for this, so I am not sure if it is possible to get it to work as an SMP client. We recommend using AuTerm when doing DFU from a computer.

A colleague has made an example showing how to do DFU from one nRF52840 DK to another using SMP client and server. These examples were last tested in nRF Connect SDK v2.2.0, so they are outdated, but they can be useful as a starting point. The code is not thoroughly tested or qualified and should be considered provided “as-is”. Please test it with your application and let me know if you find any issues. You can find it here: https://github.com/hellesvik-nordic/samples_for_nrf_connect_sdk/tree/v2.2.0/bootloader_samples/client_smp/smp_client_uart.

As for the timeout error, did you follow the DevAcademy exercise when implementing DFU over UART? If not, I recommend doing so, as this has been tested and should work. If everything is correct in your application, it could be that you have not disabled virtual mass storage, which might interfere with DFU. The baud rate and other settings in AuTerm look correct in your image. The nRF54L15 has two COM ports. Have you tried both?

Best regards,
Marte

RE: NRF54L15 - DFU over UART. Not able to update the Firmware.

varsha@ — Mon, 11 Aug 2025 13:10:54 GMT

Yes , I did try this, but I was unable to use the AuTerm application as, as I was getting the Timeout error. Also , I wanted to try manually, by writing the data into the flash, as I will be using a micro controller to send the Firmware for Update through UART.

RE: NRF54L15 - DFU over UART. Not able to update the Firmware.

Marte Myrvold — Mon, 11 Aug 2025 11:40:19 GMT

Hi,

Have you tried using AuTerm instead of TeraTerm? I recommend looking at Exercise 1 – DFU over UART in our nRF Connect SDK Intermediate course on DevAcademy. This shows how to add DFU over UART to your application and how to perform DFU using AuTerm.

Best regards,
Marte